Rats

Rats are rodents of the genus Rattus; the most common species are the Norway or brown rat (Rattus norvegicus) and the black or roof rat (Rattus rattus). They are extremely adaptable animals that have lived alongside humans for thousands of years. Their intelligence, their ability to gnaw through almost any material, and their prolific breeding make them one of the most damaging urban pests, with a direct impact on public health and on the integrity of buildings.

Identification

• Size: 20 to 40 cm including the tail.
• Weight: between 150 and 500 grams.
• Color: gray, brown, or black depending on the species.
• Tail: long, scaly, and hairless; in the Norway rat it is usually shorter than the body, whereas in the roof rat it is longer than the body.
• Habitat: the Norway rat prefers sewers, basements, and ground-level burrows; the roof rat climbs and nests in ceilings, false ceilings, and trees.

Signs of infestation

Rats are nocturnal and secretive, so they are rarely seen during the day. Spotting these signs early lets you act before the population explodes:

• Droppings: dark, capsule-shaped pellets 1 to 2 cm long, clustered near travel routes, pantries, and food sources.
• Gnaw marks: tooth marks on packaging, wood, plastic, wiring, and furniture; rodents must gnaw constantly to wear down their incisors.
• Nighttime noises: scurrying, scratching, and squeaking inside walls, ceilings, and false ceilings at night.
• Grease trails: dark smudges of body grease along baseboards and pipes they travel frequently.
• Burrows: holes about 6 to 8 cm in diameter next to foundations, gardens, and under debris, typical of the Norway rat.

Risks to health and property

Rats are among the most dangerous disease vectors in urban environments. They can transmit more than 35 diseases, including leptospirosis (through their urine, especially after flooding), salmonellosis, hantavirus, and historically the plague. Contamination occurs when their droppings, urine, and hair come into contact with food, kitchen surfaces, or stored water.

The structural damage is just as serious. By gnawing electrical wiring they cause short circuits and are a documented cause of fires; they also puncture pipes, insulation, wooden structures, and stored goods. In the food industry, the mere presence of rats can lead to penalties, product seizure, and closure of the facility by health authorities.

How Fucesa controls it

Professional rodent control is built on Integrated Pest Management (IPM), which combines several tactics rather than relying on a single poison. This delivers a lasting result while reducing chemical use:

• Inspection and diagnosis: we locate runways, burrows, entry points, and food sources to gauge the scale of the infestation.
• Bait stations: rodenticides placed in tamper-resistant, locked stations that are safe for people and pets, with regular maintenance.
• Traps: mechanical capture traps at activity points, useful where poison is not appropriate, such as kitchens and food areas.
• Exclusion: sealing entry points with gnaw-resistant materials (sheet metal, wire mesh, cement) to prevent re-entry.
• Sanitation and monitoring: removing food and water sources, plus periodic inspections to confirm there is no activity and to adjust the program.

Prevention

• Seal entry points: close cracks and openings larger than 1.5 cm, since an adult rat can squeeze through a gap the size of a coin.
• Sanitation: store food in airtight containers, manage trash in closed bins, and fix water leaks.
• Tidiness: clear debris, weeds, and cluttered storage that provide shelter and nesting sites.

When to call a professional

Seeing a rat during the day usually means the population is already large, because competition forces them out into the open. If you find fresh droppings, recurring gnaw marks, or hear nighttime noises, it is best to act immediately: a female can have several litters a year, and a single pair generates hundreds of descendants in a few months. Over-the-counter traps and poisons rarely control an established colony.

Fucesa has more than 40 years of experience in rodent control and operates in compliance with Mexican standard NOM-256-SSA1-2012 and under a COFEPRIS health license, headquartered in Toluca with coverage in Querétaro. We design IPM programs for homes, businesses, and the food industry, with certified technicians and documentation for health audits.